alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE APT/Donot Group Checkin Activity (GET)"; flow:established,to_server; http.request_line; content:"GET /access/fps_ips_cp_ifpcspf_ifis_p HTTP/1.1"; fast_pattern; http.header_names; content:!"Referer"; content:"|0d 0a|User-Agent|0d 0a|Host|0d 0a 0d 0a|"; reference:md5,209050f85af2786248bd4d7ec0f5a808; reference:md5,7be9832a01b3004f02ff5bc0691d1700; reference:url,twitter.com/h2jazi/status/1476946007741108249; classtype:command-and-control; sid:2034879; rev:1; metadata:attack_target Client_Endpoint, created_at 2022_01_10, deployment Perimeter, malware_family DonotGroup, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_01_10;)